The Promised Neverland does drag a bit, but it does finally end.

Nauiscaa is one of my all time favorites, both the manga and the movie. My dad had the comic book store special order Nauiscaa for him as it came out translated into English. He finally let me read the whole thing back around 2000/2001. I think it just had it's 40th anniversary, so that may be why it's popping up again.